Journal Article

Improved Clinical Risk Stratification in Patients with Long QT Syndrome? Novel Insights from Multi-Channel ECGs

Zumhagen, Sven, Eckardt, Lars, Gönes, Mehmet, Bruns, Hans-Jürgen, Vahlhaus, Christian, Samol, Alexander, Paul, Matthias, Waltenberger, Johannes, Mönnig, Gerold, Schulze-Bahr, Eric

2016

Overview

We investigated whether multichannel ECG-recordings are useful to risk-stratify patients with congenital long-QT syndrome (LQTS) for risk of sudden cardiac death under optimized medical treatment. In 34 LQTS-patients (11 male; age 31±13 years, QTc 478±51ms; LQT1 n = 8, LQT2 n = 15) we performed a standard 12-channel ECG and a 120-channel body surface potential mapping. The occurrence of clinical events (CE; syncope, torsade de pointes (TdP), sudden cardiac arrest (SCA)) was documented and correlated with different ECG-parameters in all lead positions. Seven patients developed TdP, four survived SCA and 12 experienced syncope. 12/34 had at least one CE. CE was associated with a longer QTc-interval (519±43ms vs. 458±42ms; p = 0.001), a lower T-wave integral (TWI) on the left upper chest (-1.2±74.4mV*ms vs. 63.0±29.7mV*ms; p = 0.001), a lower range of T-wave amplitude (TWA) in the region of chest lead V8 (0.10±0.08mV vs. 0.18±0.07mV; p = 0.008) and a longer T-peak-T-end time (TpTe) in lead V1 (98±23ms vs. 78±26ms; p = 0.04). Receiver-operating-characteristic (ROC) analyses revealed a sensitivity of 96% and a specificity of 75% (area under curve (AUC) 0.89±0.06, p = 0.001) at a cut-off value of 26.8mV*ms for prediction of CE by TWI, a sensitivity of 86% and a specificity of 83% at a cut-off value of 0.11mV (AUC 0.83±0.09, p = 0.002) for prediction of CE by TWA and a sensitivity of 83% and a specificity of 73% at a cut-off value of 87ms (AUC 0.80±0.07, p = 0.005) for prediction of CE by TpTe. Occurrence of CE in LQTS-patients seems to be associated with a prolonged, low-amplitude T-wave.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Adolescent / Adult / Aged / Biology and Life Sciences / Brugada Syndrome - diagnosis / Brugada Syndrome - physiopathology / Cardiac arrhythmia / Cardiac Conduction System Disease / Cardiology / Care and treatment / Chest / Congenital diseases / Death, Sudden, Cardiac - etiology / Death, Sudden, Cardiac - prevention & control / Deoxyribonucleic acid / Diagnosis / DNA / Electrocardiography / Electrocardiography - methods / Family medical history / Female / Genetics / Heart / Heart Conduction System - physiopathology / Heart diseases / Hospitals / Humans / Long QT syndrome / Long QT Syndrome - complications / Long QT Syndrome - physiopathology / Male / Medical diagnosis / Medical treatment / Medicine / Medicine and Health Sciences / Middle Aged / Mutation / Patient outcomes / Patients / Prevention / Prognosis / Research and Analysis Methods / Retrospective Studies / Risk / Risk Assessment - methods / Risk Factors / ROC Curve / Sensitivity / Sensitivity analysis / Sudden cardiac death / Syncope / Young Adult